CRYSTALLOGRAPHIC STUDIES OF NEUREXIN 1 _

神经毒素是神经元细胞表面蛋白质，参与 神经元-神经元识别和粘附，在建立我们的 神经网络的 Neurexin-1-_由单个结构域组成， 与任何已知结构的蛋白质序列同源。 衍射 目前在内部扩展到7 E，但使用10分钟 在SSRL 9 - 1的3E天然数据集的曝光已经收集。 一 一个有前途的铂衍生物已确定使用只有部分数据 集 我们计划收集一个完整的数据集，我们铂衍生 N-1-_晶体。 此外，由于我们的衍射差， 晶体限制什么可以在家里做，我们计划屏幕额外的 重原子衍生物 已制定详细程序， 快速筛选大量晶体。 完整的数据集将 只有在同构（和异常）差异可以 在光束线上演示。 非晶体学的存在 我们的晶体中的对称性使得即使是低分辨率的相位 对结构测定有重要意义。

Neurexins are neuronal cell surface proteins involved in neuron-neuron recognition and adhesion, critical in establishing our neural network. Neurexin-1-_ is comprised of a single domain with no sequence homology to any protein with known structure. Diffraction is poor extending currently to 7 E in house, but using 10 minute exposures at SSRL 9-1 a 3 E native data set has been collected. A promising Pt derivative has been identified using only a partial data set. We plan to collect a complete data set of our Pt derivatized N-1-_ crystals. In addition, because the poor diffraction of our crystals limits what can be done at home, we plan to screen additional heavy atom derivatives. A detailed procedure has been worked out to rapidly screen a large number of crystals. Complete data sets will only be collected if isomorphous (and anomalous) differences can be demonstrated at the beam line. The presence of non-crystallographic symmetry in our crystals makes even low resolution phases extremely valuable for the structure determination.